What to Do Immediately After Spotting a Mouse Inside Your Home
A pest prevention expert breaks it all down.
No matter your home's size, model, or age, certain pests always manage to find their way in. As for mice? According to Kari Warberg Block, a pest prevention expert and the founder and CEO of EarthKind, these rodents can be one of the more difficult types to spot. But have no fear—there are still ways to make sure mice can be detected and removed from your house. Here, Warberg Block shares what to do if you see mice in your home—and how to prevent them from coming in moving forward.
Find out where the mouse came from.
When you first catch sight of a mouse in your home, Warberg Block says the first step is to immediately find out where it came from. "Getting rid of mice is important, but it's not a solution if there is still a revolving door letting more rodents in," she says. "Since mice usually live and eat within a 20-foot area, you shouldn't have to look far." To figure out where it might have been hiding, grab a flashlight and look under your cabinets, sink, appliances (like the stove or dishwasher), and in the backs of drawers and cupboards.
Since mice often seek shelter in the undisturbed parts of your home, Warberg Block notes that you should also check these "hot spots": pantries, voids under or behind cabinets, dryer vents and ventilation systems, basement crawlspaces, attics, and insulation. "If mice are still eluding you, try this super sleuth secret: Sprinkle baby powder or baking powder on the floor wherever you think there may be mice," she adds. "When the mouse comes out of hiding, it will leave a trail of footprints, helping you identify where it came from and where it was headed," she adds.
Watch for more.
"Watch out for these telltale signs of mice: crumbs or scraps of food strewn about, greasy smudges along the wall and floorboards, mysterious holes or evidence of gnawing on food packages or boxes, squeaking or scurrying sounds, and droppings that look like black grains of rice," Warberg Block says of figuring out if you have an infestation on your hands. Other key signs? A musky smell or urine odor. If you spot shredded supplies, like paper, you've likely found their breeding ground (mice usually use the material to make nests for their offspring). Your pets can even help play detective in this type of situation. "Dogs can detect a mouse in the house even when we can't, so if your Fido is focused on a certain spot or scratching at the floor, you'll want to take a closer look," she notes.
Another way to tell if you have a family of mice living alongside your own? You see mice during the day. This is indicative of larger numbers, since mice typically scavenge for food at night. Spotting a mouse or two in broad daylight means they didn't get enough to eat the night prior (these mice are weaker) and likely got pushed off dinner by their more dominant (and numerous) counterparts. Warberg Block also explains that mice multiply at a rapid rate, so you need to act fast if you notice one or more. "Female mice can reproduce when they are just two months old and can give birth to a litter every six to eight weeks," she says. "Each litter averages between two to 12 baby mice, so even if it starts as a few mice in your home, it can quickly grow into a major infestation."
Though Warberg Block prefers to implement natural pest prevention measures to keep mice out of your home entirely, extermination is, unfortunately, sometimes necessary. If you have reached this point, hire a pest control professional. It's important to call an expert as soon as you notice an outbreak, since mice can carry over 35 different types of diseases and can potentially harm the structure of a home by chewing on electrical wires—which could cause house fires. Just make sure you proceed with caution regardless, whether you're tackling this process yourself or hiring an exterminator. Warberg Block recommends following the Centers for Disease Control and Prevention's (CDC) guides to properly exterminate on your own and clean up after the infestation. "If you do choose to use a trap, I advise using a humane live trap," she adds.
Prevent them from coming back.
Spotting mice and trapping them is more difficult than keeping them out of your home, which is as easy as one, two, three in Warberg Block's book. The best way to block the rodents from coming into your home is by making your space less attractive to them in the first place—this means limiting their access to food, water, and shelter. "This is done by sealing off their entry points, cleaning up their food sources, and using plant-based pest repellents to create a protective barrier," she says. Begin by sealing any small cracks or openings around your home with steel wool—you can spot these gaps by looking around your walls, windows, doors, utility lines, and your house's foundation. Mice can't chew through this material (it irritates their teeth), Warberg Block explains. Then, seal around the opening with caulk and weatherstrip your doors and windows. Place plant-based repellents like EarthKind Stay Away Rodent ($25.80, earthkind.com) in your house or Fresh Cab Botanical Rodent Repellent ($59, earthkind.com) for more isolated areas (including garages and attics) instead of poisons or traps. "Simply place one pouch per 125 square feet in areas you want to keep rodent-free, and rest easy while you enjoy 30 days of protection," Warberg Block adds.
The last step is to keep your home clean, especially when it comes to food. Many people have loaded their pantries with essentials during the COVID-19 pandemic—think extra toilet paper, dried foods, dog food, seeds, and more—and Warberg Block says this is the best possible environment for mice when the weather turns cold. "Dog food is the number one rodent attractant, so start by cleaning up areas where traces of pet food may be present to eliminate attractants that lure them in," she shares. "Transfer dry foods into an airtight, chew-proof glass, metal, or plastic containers and place them high up in the pantry for added protection." Also make sure to fix any leaky faucets and pipes since mice are drawn to a water supply—and declutter as much as possible so they won't have places to hide. "When you use proactive pest prevention measures [like these], it's less likely rodents will ever enter—or if they do, they'll turnaround and leave on their own." Warberg Block says that mice even leave scent markers that signal to other mice that it isn't safe to enter your home.